Auto duplex reproduction machine

Abstract

An integral removable duplex module for use in conjunction with a reproduction processor is disclosed including two paper trays, a first operable as a duplex copy buffer tray or a paper tray and a second operable as an auxiliary paper tray, each tray having a copysheet feeder associated therewith comprised of a single cam operated mechanism having two cantilevered arms supporting constantly rotating feed rollers suspended above each paper tray and associated tray elevator mechanisms which enhances copysheet feeding when the feed rollers are pivoted toward the trays into copysheet feeding position and maintain copysheet trays in non-feeding positions during non-feeding operation. Copysheets are received in the duplex copy buffer tray from the reproduction processor via a reversible exit nip at the output of the processor, which directs sheets passed to an output back to a duplex module paper path, for repassing through the reproduction processor. Papers entering the module may be directed to either the duplex copy buffer tray or a trayless path which passes copysheets directly back to the processor. A method for operating the duplex module is described to efficient use of the trayless path, by directing copysheets thereto depending on the number of copies to be made. Accordingly, copysheets may be directable to the duplex tray or trayless path at various times during any run. Further use of the trayless path is made to advantageously improve two-up copying feature paper handling. Duplex operations are disabled on separation of the module from the reproduction processor.

What is claimed is: 
     
       1. A method of copying original documents onto both sides of copysheets to produce duplex copysheets including the steps of: determining the number of copies to be made from an original document;   copying images from said document onto the first sides of copysheets at said copying station;   passing copysheets bearing an image on said first side thereof to a duplex paper path to return said sheets to said copying station, said duplex paper path having at least two selectable copysheet paths including a first copysheet path returning said copysheets directly to said copying station, and said second copysheet path passing said copysheets to a duplex buffer tray for storage prior to returning said copysheets to said copying station; and   selecting one of said first and second copysheet paths and directing said copysheets thereto in response to a predetermined condition.   
     
     
       2. The method as described in claim 1 wherein said copysheets bearing an image on said first side thereof are passed to said first copysheet path when fewer than a preselected number of copies are to be made. 
     
     
       3. The method as described in claim 1 wherein said copysheets bearing an image on said first side thereof are passed to said first copysheet path when said documents to be copied is simplex. 
     
     
       4. The method as described in claim 1 wherein said copysheets bearing an image on said first side thereof are passed to said first copysheet path when said documents to be copied are of a preselected size. 
     
     
       5. The method as described in claim 2 wherein said copysheets bearing an image on said first side thereof are passed to said second copysheet path when the number of pages of said document to be copied is greater than a predetermined number. 
     
     
       6. The method as described in claim 1 wherein said copysheets bearing an image on said first side thereof are passed to said second copysheet path when the number of pages of said document to be copied are greater than about 2. 
     
     
       7. The method as described in claim 6, and including selecting said first path and directing said copysheets thereto in response to a second preselected condition occurring while said document is being copied. 
     
     
       8. The method as described in claim 7 wherein said second preselected condition occurs when only a selected number of pages of said document remain to be copied. 
     
     
       9. A method for copying simplex documents placed side by side on a platen to produce duplex copies therefrom in a reproduction machine provided with an reproduction processor for making copies of scanned documents including a copysheet input and a copysheet output, a controllable optics assembly for selectively scanning images from either of said documents placed on said platen, inverting means for inverting copysheets received from said copysheet output and bearing only a first side image, and a trayless paper path for directing copysheets bearing said first side image from said inverting means to said copysheet input to receive a second side image, including the steps of: (a) placing first and second simplex documents onto a copying platen in side by side relationship;   (b) scanning a selected one of said first and second document, with said controllable optics assembly, a preselected number of times to produce an equivalent number of copysheets bearing an image from said selected document on a first side;   (c) passing said number of copysheets through said inverting means and said trayless paper path to return said copysheets to said reproduction processor for receiving an image on a second side thereof;   (d) scanning the other document said preselected number of times to produce an image on said second side of said copysheets; and   (e) passing said copysheets bearing first and second side images to an output.   
     
     
       10. The method as defined in claim 9 and further including the step of repeating steps (b) through (e) until a desired number of duplex copies of said first and second simplex documents are obtained. 
     
     
       11. The method as defined in claim 10 wherein said optics assembly scans said first document a maximum of two times before scanning said second document. 
     
     
       12. A method for making duplex copies of documents in a reproduction machine including a reproduction processor having, a duplex module including a duplex buffer tray and a trayless path and a duplex path for carrying paper or copysheets held in said duplex buffer tray and a trayless path to the reproduction processor to receive images thereon, a copysheet path for selectably carrying copysheets from said reproduction processor to either of an exit means and said duplex module, deflector means in said duplex module for directing copysheets from said reproduction processor to one of said duplex buffer tray and a trayless path, the method comprising the steps of: (a) providing blank paper for receiving a first image thereon in said duplex buffer tray;   (b) passing said blank paper from said duplex buffer tray to said reproduction processor;   (c) returning said paper bearing first images thereon to said duplex module;   (d) directing said paper to the trayless paper path;   (e) passing said paper back to the reproduction processor to receive a second image;   (f) directing said paer having two images thereon to an exit means.   
     
     
       13. The method as defined in claim 12 and including the step of: holding said paper in said trayless paper path until a control signal indicates that it is to be passed back to the reproduction processor to receive a second image.   
     
     
       14. A method of making duplex copies in a reproduction machine having having a reproduction processor, a duplex tray and a trayless path, and means for selectably choosing to pass simplexed copy sheets through one of said duplex tray and trayless path to return said copy sheets to said reproduction processor to receive second side images thereon, and operating in accordance with the following sequence:   ______________________________________                                    
        Simplex/ Simplex/    Duplex/                                      
                                    Duplex/                               
        Duplex   Duplex      Duplex Duplex                                
Paper Size                                                                
        RL ≦ 2                                                     
                 RL > 2      RL ≦ 2                                
                                    RL > 2                                
______________________________________                                    
A5      Trayless Trayless    Trayless                                     
                                    Trayless                              
A4 or   Trayless Trayless    Trayless                                     
                                    Stacked                               
letter                              except last 2                         
size LEF                            copies run                            
                                    trayless                              
A4 or   Trayless Stacked     Trayless                                     
                                    Stacked                               
letter           except last 2      except last 2                         
size SEF         copies run         copies run                            
                 trayless           trayless                              
B4 or   Trayless Stacked     Trayless                                     
                                    Stacked                               
Legal            except last 2      except last 2                         
                 copies run         copies run                            
                 trayless           trayless                              
______________________________________                                    
     
     
     
       15. The method as defined in claim 9 and including the step of: holding said paper in said trayless paper path until a control signal indicates that it is to be passed back to the reproduction processor to receive a second side image.